Excavating bucket adapter for replaceable tooth points



P 21, 1954 A. w. DANIELS ETAL ,689,419

EXCAVATING BUCKET ADAPTER FOR REPLACEABLE TOOTH POINTS Filed Jan. 12,1950 3 Sheets-Sheet l p 21, 1954 A. w. DANIELS ETAL 2,689,419

EXCAVATING BUCKET ADAPTER FOR REPLACEABLE TOOTH POINTS Filed Jan. 12,1950 3 Sheets-Sheet 2 P 1954 A. w. DANIELS ET AL 2,689,419

EXCAVATING BUCKET ADAPTER FOR REPLACEABLE TOOTH POINTS Filed Jan. 12,1950 3 Sheets-Sheet 3 IN V EN T 0R6 (Z'Zkar W 2762124625,Masgo/zP/Varlzzg/Z,

Patented Sept. 21, 1954 UNITED STATES PATENT OFFICE EXCAVATING BUCKETADAPTER FOR REPLACEABLE 'roorn POINTS Arthur W. Daniels, Wilmette,

Murtaugh, Pacific Palisades, Calif., to American Brake Shoe Company,

111., and Joseph P.

assignors New York,

N. Y., a corporation of Delaware Application January 12, 1950, SerialNo. 138,238 4 Claims. (01. 37-142) Many types and designs of two-partteeth for use on excavating implements have been developed over the lastseveral years. More recently the trend has been toward a small, lowcost, renewable point combining the features of economy with diggingefliciency and which will provide a thin cutting edge for easypenetration into the material to be excavated. From an engineering anddesign standpoint there are two important features which have militatedagainst arriving at the ultimate in perfection where a replaceable pointis desired, the first being the inherent weakness of the nose portion ofthe adapter which necessarily has .to be correspondingly small toaccommodate the point, the second being the necessity of using highalloy steels difierentially and specially heat treated to provide thehardness necessary and the stifiness required to avoid bending anddeformation.

Accordingly, it is an object of the invention to provide a two-partexcavating tooth which will be economical to manufacture althoughdurable and rugged in service, and which will essentially consist of anadapter providing a nose portion of novel design and a replaceable pointhaving a cavity of complementary shape for interfitting relation withthe nose portion. In the excavating tooth of the invention the weight ofthe man ganese steel employed in the parts is kept to a minimum althoughadequate metal section is provided of the proper contour and shape totake advantage of all the good qualities of the metal and at the sametime strengthen the parts against bending or deformation of any kind.

Another object of the invention is to provide a replacable point for anexcavating tooth which is reversible on the nose portion of its adapterand wherein the design of said point and nose portion is such as tolocate the greater portion of the metal where it is available for wearand to employ the minimum amount of metal for holding purposes.

Another object resides in the provision of a box-like replaceable pointfor excavating teeth which will have slotted openings in the top andbottom walls thereof to permit interlocking of all four inside cornersof the point with overlapping ribs onthe adapter, and wherein anincreasingly tight fit of the point on the adapter is obtained aspressure is applied in digging as a result of the tapering fit betweenthe point and the adapter for the full length of the nose portionthereof.

A further object is to provide a composite excavating tooth wherein theadapter or base mem-' ber has a nose portion of novel and. improveddesign with the metal being so distributed and proportioned thatadvantage is taken of the total depth and most of the width of the noseportion at the point of greatest stress and leverage whereby toefiectively resist shock loads imposed from all directions.

A further object is to provide a replaceable 'point for an excavatingtooth for interfitting relation with the nose portion of an adapter orbase member and which is symmetrical about horizontal and verticalcenter lines, whereby the metal section at the top and bottom is equalfor maximum strength of the point and for protection of the noseportion, and wherein the said point is so shaped and located on the noseportion as to automatically sharpen itself as a result of normal diggingoperations.

Another object of the invention is to provide a composite toothcharacterized by the nose portion of the adapter being disposed at anangle in a downward direction with respect to the lon gitudinal centerline of the composite tooth,

whereby the practicability of the self-sharpening feature of thereplaceable point is improved, and' clearance is maintained at all timeson the underside of the tooth to prevent any tendency of the adapter toforce the digging point out of the work.

A further object resides in the provision of a replaceable digging pointfor a composite tooth which will have side edges of greater thicknessthan the center portion with no fiat surfaces top or bottom, and whereinthe outside corners are extended beyond the center portion to compensatefor the increased wear on the metal at the outside corners. When saidoutside corners are worn as a result of initial digging operations toprovide a straight cutting edge, the entire cutting edge of thereplaceable point will be workhardened under impact to approximatelytwice its original hardness and the cutting edge will continue to wearsharp for the entire life of the point.

With these and various other objects in view, the invention may consistof certain novel features of construction and operation as will be morefully described and particularly pointed out in the specification,drawings and claims appended hereto.

In the drawings which illustrate an embodiment of the invention, andwherein like reference characters are used to designate like parts-Figure l is an exploded view illustrating in perspective the parts ofthe present composite tooth comprising the adapter, the replaceabledigging point and the locking key;

Figure 2 is a top plan view of the composite tooth with the parts inassembled relation;

Figure 3 is a fragmentary side elevational view of the nose portion ofthe adapter in assembled relation with the replaceable point as shown inFigure 2;

Figure 4 is a top plan viewof the replaceable point;

Figure 5 is a vertical sectional view of the replaceable point takenlongitudinally along line 55 of Figure 4;

Figure 6 is a horizontal .sectional View of the replaceable point takenalong line 6-6 of Figure 5;

Figure 7 is a vertical, transverse sectional view along line il ofFigure 3 illustrating the interfitting relation of the replaceable pointwith the nose portion of the adapter;

Figure 8 is a vertical, transverse sectional view taken along line 88 ofFigure 3;

Figure 9 is a vertical, transverse sectional view taken along line 9-9of Figure 3;

Figure 10 is a perspective view showing a modified form of replaceablepoint characterized by edge portions of increased thickness with theoutside corners being extended beyond the center portion; and

Figure 11 is a' transverse sectional view, somewhat enlarged, takenalong line ll-H of Figure In the illustrated embodiment of the compositetooth selected for illustrating the present invention the adapter orbase portion indicated by numeral 29 is provided with a rearwardlyextending tang 2! having a verticalkeyway slot or opening 22 ofconventional design and construction whereby the adapter may bedetachably mounted on the forward digging lip of excavating buckets,shovels, dippers and the like as will be well understood by thoseskilledin the art. In accordance with the invention theadapter 20 has anose portion 23 of special shape andwhichnose portion has internttingrelation with the replaceable digging point 2 it being understood thatthe parts are assembled by relative longitudinal movement, the noseportion 23. fitting into a cavity located in the rear of the replaceablepoint.

The cavity in said replaceable. point is also of special design, havinginwardly protruding lugs and recesses whereby the cavityis complementaryin shape to that of the nose portion.

As illustrated in Figures 1 and 3, the nose portion is disposed on theadapter. 20 at a slight angle in a downward directionwithrespect to thelongitudinal center line of the composite tooth, the angle beingindicated by A in Figure 3. The purpose of this construction is toprovide clearance on the underside of the cutting point. This is animportant feature of the present design of composite tooth since itresults in a greatly improved digging point and at the same time itenhances the practicabilit of the self-sharpening feature of the point.Also the box-like construction of the replaceable point makes itpossible to-reverse the position of the sure is applied to the point.

The self-sharpening feature of the cutting point,

together with the clearance which is maintained on the underside of thepoint eliminates any tendency of the base member or adapter to force thedigging tip out of the work digging operations.

Referring more particularly to Figures 1, 2 and 3, the nose portion 23of the adapter is characterized by a web 26 which extends forwardly oftheadapter, being nose-shaped in side elevation and disposed centrallyon the vertical center line. The web 26 gradually merges into the topand bottom surfaces El and 29 of the adapter. However, at these pointsthe web widens out to provide overlapping ribs 28 of arcuate shape asregards their periphery and which taper at their base. where they jointhe adapter to a substantially thin edge at the forward extremity wherethe ribs merge with the web. Four overlapping. ribs 2.8 are provided,two on each side of the web,

one at the top and one at the bottom. It will.

characterized by laterally projecting lugs 39, having location oneachside of the web 25, and being centrally positioned with respect tothe longitudinal center line of the nose portion. At their base 35,where the lugs. join-the adapter, they have considerable width and'itwill be observed that the lugs on each side of the web. are.

similar in shape and that they taper. rather abruptly in a. directionforwardly of the nose. portion, In fact, the lugs extend beyond thefor-.

ward edge of the nose portion where they join.- to form the tongue 32..The top and bottom surfaces 33 and 34,.respectively, of each lug 3Uslope in a direction inwardly toward the web 26. Each lug therefore hasits greatest thickness along its outer extremity. In other. words, thethickness of the lug at its outer extremity is greater than thethickness of the. lug at a comparative point adjacent the web. Thisconstructional ,fea-- ture is perhaps best shown in Figures 7, 8 and'9,and an important advantage'thereof is to improve the interfittingrelationwhich the replaceable point has'on the nose portion, whichbecomes increasingly tight as greater digging pres- The transverseopening 35 provides a keyway for receivingthe key 36. by means of whichthe'replaceable point is releasably locked in assembled relation on thenose portion of the adapter.

The replaceable point 2 5 is of box-like formation. having top andbottom walls 49 and M and side-walls 42 and 43. Each side Wall isprovided' with a central boss portion 44 projecting laterally on theoutside surface-thereof and having location so as to extend slightlybeyond.

the rear edge 65 of the replaceable point; The

boss-like portion has the effect of thickening each wall at its locationand the same is apertured to provide the keyway slot 46. The key.-

way slots in the side walls 42 and 43 are of course ing key 36. The keyis slottedlongitudinally,to.

The replaceable point 24 is locked on the nose portion 23 by the taper-=provide the spaced prongs 41 and 48, there being located between theprongs a resilient insert 50 of rubber or other suitable material toapply tension to the prongs when compressed. Prong 41 at its terminalend is notched as at 5| so that the key 36 upon being inserted throughthe aligned keyways to its full extent will have locking relation with aside wall of the nose portion as a result of the resilient tensionexerted by the prongs of the key. The full taper of the key 36 isapplied to prong 48 and the transverse keyway I5 is similarly tapered sothat it is impossible for the operator to insert the key in an impropermanner.

The cavity in the rear wall of the replaceable point is best illustratedby Figures 1, 5 and 6. As previously explained, said cavity has a shapewhich is complementary to that of the nose portion. The cavity ischaracterized by longitudinal slots 52 in the top and bottom walls 40and 4|, the slotted openings receiving the web 26. It will be observedthat the entrance to each slotted opening is formed by spaced walls 53,which diverge in a direction toward the rear, each wall being slightlydished to provide an arcuate contour for receiving an overlapping rib28. This structual feature permits interlocking of all four insidecorners of the replaceable point with the overlapping ribs on theadapter. Each side wall within the cavity is recessed as at 55 and 56,each recess extending from the rear wall 45 in a forward direction andterminating in the transverse groove 51. The recesses 55 and '56 taperin a forward direction from the rear Wall 45 toward the cutting edge ofthe point, each recess terminating in the groove 51, which in effectconnects the recesses in a manner similar to the connection of the lugs30 by tongue 32. In fact, the recesses are designed to receive the lugs30 and accordingly they have a shape complementary to the lugs with thegroove 51 receiving the tongue 32. The top and bottom surfaces 58 and 59of each recess slope in a direction outwardly toward their side walls,and it will be seen from Figures '1, 8 and 9 that the slope is such asto accommodate the lugs 30 to provide a close and tight fit between thecoacting surfaces of the respective parts.

The recess formed in each side wall of the replaceable point incombination with the slottedopening in the top and bottom walls producelugs that protrude inwardly of the cavity. Said lugs extend on each sidewall from the rear wall 45 to adjacent the groove 51. The lugsprotruding inwardly from the side wall 42 and which form the recess 55are indicated by numerals 60 and 61, constituting the top and bottomlugs respectively. In a similar manner the lugs protruding inwardly fromthe side wall 43 and which form the recess 56 have been indicated bynumerals 62 and 63, comprising the top and bottom lugs, respectively. InFigures 8 and 9 it will be seen that each lug for a, part of its lengthhas a substantially flat and horizontal outer surface although theinside surface of each lug slopes in a direction outwardly toward itsside wall. The flat surface of each lug is provided for receiving anoverlapping rib 28, the coacting surface of each overlapping riblikewise being flat and substantially horizontal for the purpose.

The modified form of replaceable point generally indicated by numeral64, as shown in Figures 10 and 11, is characterized by side edges 65 ofincreased thickness which extend from approximately the center of thepoint forwardly to the cutting edge. Also the outside corners 66 of thecutting edge have been extended beyond the center section 61. It must beremembered that manganese steel work-hardens under impact and also thatthe outside corners of the cutting edge wear faster than the centralsection, Thisis due to the breakdown of the metal at the outside edgeswhere there is no support and the condition is particularly true asregards manganese steel due to the ductility and surface softness of themetal. It is well known in actual practice that when the outside cornersof the cutting edge wear away during initial stages of operation, atooth results having a blunt, rounded cutting edge that exists for theentire life of the tooth. The purpose of th modified design of point isto provide more wear metal at the points of greatestwear andadditionally to make the outside edges of the point, both top andbottom, as well as the forward cutting edge take the initial wear andimpact and work-harden to the extent that when the cutting edge isapproxi- 'm=ately straight across the same will be workhardened underimpact. From there on the point will have a sharp cutting edge whichwill be straight for its entire width with no rounded corners and whichcutting edge will have about "twice the hardness of a new point andwhich will continue to wear sharp for the entire life of the same.

The invention is not to be limited to or by details of construction ofthe particular embodiment thereof illustrated by the drawings as variousother forms of the device will of course be apparent to those skilled inthe art without departing from the spirit of the invention or the scopeof the claims.

What is claimed is:

1. A tooth for excavating implements or the like including an adapterconsisting of the conventional base portion and a nose portion ofspecial shape and design for receiving a replaceable point, said noseportion including a forwardly projecting nose-shaped webdisposed'vertically on the center line of the base portion, an integrallug on each side of the web protruding laterally of the web and taperingin a forward direction from the base portion to beyond. the web wherethe lugs join to form a tongue, said tongue being disposed substantiallynormal to the web, each lug being disposed centrally of the web andbeing symmetrical with respect to the longitudinal center line of thenose portion, the top and bottom surfaces of the lugs sloping laterallyinward in a direction toward the web whereby said lugs have theirgreatest vertical dimensions along the outer surface thereof, anintegral rib on each side of the web above and below the lugs adapted tohave overlapping relation with a portion. of said replaceable point whenthe parts are assembled, said overlapping ribs each having location atthe junction of the web with the base portion, each rib projectinglaterally to one side of the web and forwardly of the base portion, andsaid replaceable point having a rear cavity of complementary shape forinterfitting with the nose portion, said cavity including a forwardrecess for receiving the tongue of the nose portion.

2. A tooth for excavating implements and the like as defined by claim 1,wherein said overlapping ribs have a periphery substantially arcuate incontour, and wherein each said rib has its greatest thickness adjacentits connection with the base portion and tapers in a forward direc- 7tion:to;.-a:relatively:thim edge at its extreme, for- Ward endwhere'=:the rib-merges with the web.

r13. A-.tooth1for excavatingdmplements and the like .as=:defined byclaim I 1, wherein said overlapping ribsihaveza periphery substantiallyarcuate .:in;contour, 'wherein each rib has its greatest thicknessadjaeentits :connection with the base portiontandtapers imaforwarddirection to a relatively thin edge .at its--extreme forward ,end "where:the ,rib {merges with a the web, and additionally vincluding a:transverse keyway for receiving a ekey whereby to lock the replaceable.pointin -assembledrrelationeon the nose portion, said :transversekeywayincluding .a passage gexytending-flthrough.theilugsgand.the web: on thelongitudinal centerlineofthenose portion.

.1sl.-.-A.;to.oth for excavating implements and thelikelincludingganradapter consisting of the conventionallbase portionand ,awnose portion, of spe- .point, said nose portion including a,forwardly projecting nose-shapedwebdisposed vertically on the reenterline of thebaseportion, an integral lug on each-side of 'the webprotruding laterally of the shape inside elevation simulating, atriangle with the base of the same being located adjacent the cialshape-and designv forreceiving a replaceable 2O-baSe;portionlanditheItohgueformingtheapex 1th,e

top andi-bottomsurfaces of the lugs slopingulaterally inwardina.direction toward the web whereby the lugs have their-greatest Verticaldimensions along their outer surface; an integral. riboneach side of theweb above and below the'lug on that side and adapted tohave overlappingrelation with a portion of said replaceable point When the parts areassembled, said overlapping "ribs each occupying the angular spaceformed by the junction of the web with the base portion, andsaid ribseachtapering .in -a forward direction whereby to provide a relativelythin edge at the extreme forward end of the rib where the rib meres-with the web.

References Cited 4. in t thev file of this patent UNITED STATESv'PATlilN'IS Number Name 1,Date

821,215 Cantlebery et'al. May,22,'1'90.6 1,202,806 Clark, (Jr. 2 Oct.31,1916 1,205,969 Brinton Nov. 28,1916 1,330,143 Seal Feb. 10,19201,548,374- Mullally 'Aug. 4, 1925 1,845,677 'Mekeel Feb. 16, 19322,256,488 Murtaugh Sept.23, 194.1 2,279,960 Terry Apr.'14, 1942"2,435,847 Robertson Feb. 10, 1948

